Galactic rain could be key to star formation

Washington: Some of the galaxies in our universe are veritable star nurseries. For example, our own Milky Way produces, on average, at least one new star every year. Others went barren years ago, now producing few if any new stars. Why that happens is a question that has dogged astronomers for years. Scientists say that precipitation might be the reason behind it. Obviously it’s not in the form of rain or snow, but rather cool gas that helps make the creation of stars possible. When conditions are right, these cooling gas clouds help make stars.